Stars were spotted all over the stage and the runway on Friday (Sept. 22) as they took part in some of the day’s big events: the 2017 iHeartRadio Music Festival in Las Vegas, and Milan Fashion Week in Milan, Italy.

Lorde was also spotted performing in Las Vegas on Friday, as she took part in Day 1 of the 2017 Life is Beautiful Festival. Meanwhile, Noah Cyrus was spotted performing in Pittsburgh, Pennsylvania during Katy Perry‘s Witness Tour.

Later that night, Kaia and her mom Cindy Crawford were also spotted taking part in some of the Milan Fashion Week festivities at Vogue Italia’s party, where actresses Kat Graham and Arielle Kebbel also made appearances.

Check out all of yesterday’s star sightings below!

Harry Styles hit the stage in Las Vegas, Nevada on Friday (Sept. 22) to perform during Day 1 of the 2017 iHeartRadio Music Festival.

Picture: Getty Images

Kendall Jenner was spotted walking the runway on Friday (Sept. 22) at the Versace fashion show during Milan Fashion Week.

Picture: Getty Images

Kendall Jenner also walked the Tod's show on Friday (Sept. 22) during Milan Fashion Week in Milan, Italy.

Picture: Getty Images

Kendall Jenner also walked the Tod's show on Friday (Sept. 22) during Milan Fashion Week in Milan, Italy.

Picture: Getty Images

Gigi Hadid strut her stuff on Friday (Sept. 22) during the Versace fashion show at Milan Fashion Week.

Picture: Getty Images

Gigi Hadid strut her stuff on Friday (Sept. 22) during the Versace fashion show at Milan Fashion Week.

Picture: Getty Images

The girls from Little Mix (Jade Thirlwall, Leigh-Anne Pinnock, Jesy Nelson and Perrie Edwards) made an appearance in Las Vegas, Nevada on Friday (Sept. 22) during Day 1 of the 2017 iHeartRadio Music Festival.

Picture: Getty Images

Bella Hadid was spotted walking the runway on Friday (Sept. 22) during the Versace fashion show at Milan Fashion Week.

Picture: Getty Images

Lorde was also spotted on-stage in Las Vegas, Nevada on Friday (Sept. 22), as she performed during Day 1 of the 2017 Life is Beautiful Festival.

Picture: Getty Images

Singer Bebe Rexha was all smiles on Friday (Sept. 22), as she performed during Day 1 of the 2017 iHeartRadio Music Festival in Las Vegas, Nevada.

Picture: Getty Images

Noah Cyrus shined in silver on Friday (Sept. 22), as she performed during Katy Perry's Witness Tour in Pittsburgh, Pennsylvania.

Picture: Getty Images

Taylor Hill hit the runway again on Friday (Sept. 22), as she walked the Versace fashion show during Milan Fashion Week.

Picture: Getty Images

Singer Kelsea Ballerini stepped out in Las Vegas on Friday (Sept. 22) to check out Day 1 of the 2017 iHeartRadio Music Festival.

Picture: Getty Images

Model Kaia Gerber worked the runway on Friday (Sept. 22) as she walked the Versace show during Milan Fashion Week.

Picture: Getty Images

Model Kaia Gerber worked the runway on Friday (Sept. 22) as she walked the Versace show during Milan Fashion Week.

Picture: Getty Images

Later that night (Sept. 22), Kaia Gerber joined her supermodel mom Cindy Crawford on the red carpet for Vogue Italia's The New Beginning Party during Milan Fashion Week.

Picture: Getty Images

Actress Kat Graham looked radiant in red on Friday (Sept. 22), as she attended Vogue Italia's The New Beginning Party during Milan Fashion Week.

Picture: Getty Images

Former Big Time Rush member James Maslow hit the stage in Las Vegas on Friday (Sept. 22) to perform during Day 1 of the 2017 iHeartRadio Music Festival.

Picture: Getty Images

Actress Arielle Kebbel popped up in Milan, Italy on Friday (Sept. 22), where she attended Vogue Italia's The New Beginning Party during Milan Fashion Week.

Picture: Getty Images

Boy band PRETTYMUCH were spotted in Las Vegas on Friday (Sept. 22), where they made an appearance at Day 1 of the 2017 iHeartRadio Music Festival.